Ink and process of making the same



Patented Mar. 221927.-

' MATTHEW S. HOPKINS, OF READING,

PENNSYLVANIA, ASSIGNORS 'TO PHILADELPHIA, PENNSYLVANIA,

AND NORMAN UNDERWOOD, OF SWAR'IHMORE, CHARLES ENEU' JOHNSON AND COMPANY,OF A CORPORATION OF PENNSYLVANIA.

INK AND PROCESS OF MAKING THE SAME.

No Drawing.

This invention relates to the manufacture of printing inks in which 1tis of prime 1mportance to produce a compound which shall I 1 compound.This is regardless of whether the be stable in its physicalcharacteristics and .5 not deteriorate before its use by the printer. Itis also important that the compound shall not undergo chemicaldecomposition but shall remain properly preserved during the period ofstorage.

Printing inks have, as a general rule, been made from substances which,in themselves, are highly inflammable and consequently there isconsiderable fire risk in their storage and use. While it is possible toguard against undue fire risks in ordinary printing and while compoundsfor ordinary use do not necessarily carry volatile inflammableingredients, nevertheless there is a wide demand for ink known asrotogravure intaglio ink which is used on high speed rotary pressesfollowed by 'resulting'in' e volatilization of the inflammable mediums.We' have found that a satisfactory ink for this and analogous uses 85can be com ounded from materials in which the fire ris is a minimum andyet without sacrifice of the improved results desired.

.It is also a purpose of this invention to avoid the use of compoundsxylol and the like, which are expensive, and

combine with dangerous inflammability, undesirable odors which ofttimesbecome distressing tothe workmen. I

A ecial use to which our invention has been ound of material benefit isin intaglio" printing, commonly known in the trade as rotogravureprinting. In this work it is essential 'thatthe ink fill the engraved.portions of the printing plate and that the surq lus be readily wipedfrom the smooth sur-,

ace." We have found that the compound roduced asv described in thisspecification as the minimum adhesion to the smooth printing surface andis wiped clean from the 5. unen aved parts leaving an ample quantity ofi to give the desired impression on the a r. V p e basis of ourinvention consists in com- :bining with an oily coloring compound. an 9aqueous solution in the nature of a binder, producing an emulsion of thetwo capable of being thinned out to any desired degree and peration andstill to remain smooth and workable.

(pluck drying by artificial means t for example.

Application filed June 19, 1924. Serial No. 720,935.

Tliere is the added advantage that the binder increases the bindingproperties of such gums as may be used in the coloring coloringcompoundis a-mixture of pigments gums and medium or pigment and gum in medium.

As an example of one manner in which our invention may be carried out,we take the following materials in the proportions stated by weight:

2 Van Dyke brown. 7

2 gilsonite (solidasphaltum) 1 liquid asphaltum.

2 kerosene.

The liquid asphaltum, when combined.

with kerosene or an analogous oily vehicle,- will accomplish thesolution of the gilsonite, giving the necessary flow, et cetera, thatheretofore has onl been obtained through the employment. of xylol andgilsonite. To this is added the Van Dyke brown as a further coloringredient.

A bindin composition is prepared irom a water-solu le albuminoussubstance as fol lows. While it is possible to use various compounds ofthis description we have found that casein forms a satisfactory.starting point. A solution of casein is formed .from the following partsby weight:

375 casein. v

41 borax.

45 ammonia.

25 sodium'fluoride.

Fiveiiiartsbyweight of'this solution are thoroughly mixed with sevenparts by wei ht of the coloring compound above descri ed and the'mixtureis then'thinnd to thev proper consistency with a'naphtha, with thedesired boiling point, or an analogous as substance. The mass is thenthoroughly mixed by grinding, milling and thelike.

This compound has the physical properties of an emulsion possessingsuperior properties of sus nsion, thus preventin strati- Te largeproportion 0 water causes a minimum of fire risk. No ingredient is usedwhichwonld produce an in- V flammable vapor or objectionable odor. The

product works well into the engraved por- .tions of the printing plate,the excess is readil removed and there'is an effective transfgr from theplate to the paper. The

is a true solution of 60 formula for the casein solution is 'suchas toinsure its stability and, good keeping qualities. Furthermore "thecasein solution co-operates in the fixation of the'ink to the paper inthat under the temperatures at which intaglio printin is carrie outthere is quicker drying of the compound and an insolubility attainedwitha permanent water-proof bond to the paper.

It is characteristic of the ink thus formed that there is a uniformparted to the entire substance as finally used. When this is applied toiutaglio or relief printing, the effect is heightened. The ink is alsoreasonably safe from fire risk on account of the constitution above setout, while it is-convenient,and satisfactory for handling from theviewpoint of the pressman. The readiness with which satisfactorpermanent impressions are made at-hig speeds makes for eflicientresults.

intense color 1m- It will be evident that numerous substitutions can becarried out in the materials used and that reasonable latitude ispossible in the proportions taken without departing from the s irit ofthe invention and its scope as define in the following claims.

What we claim ,is:

1. An emulsified ink composed of a co1- oring compound having an oilymedium, an an aqueous solution of casein, borax, am-' monia and sodiumfluoride.

ing in incorporating a SOlld asphaltum in a mixture of liquid asphaltumand kerosene, and emulsifying the product with anaqueous solution ofcasein, bot-ax, ammonia and so,- dium fluoride. v

In testimony whereof we have hereunto affixed our signatures. v

' MATTHEW S. HOPKINS.

NORMAN UNDERWOOD.

